I have to scan it more than once


#1



cashRegister.scan("eggs",4);


#2

var cashRegister = {
total:0,
lastTransactionAmount:0,
//Dont forget to add your property
add: function(itemCost) {
this.total += itemCost;
this.lastTransactionAmount = itemCost;
},
scan: function(item,quantity) {
switch (item) {
case "eggs": this.add(0.98 * quantity); break;
case "milk": this.add(1.23 * quantity); break;
case "magazine": this.add(4.99 * quantity); break;
case "chocolate": this.add(0.45 * quantity); break;
}
return true;
},
//Add the voidLastTransaction Method here
voidLastTransaction : function(){
this.total-=this.lastTransactionAmount ;
}

};

cashRegister.scan('eggs',1);
cashRegister.scan('milk',1);
cashRegister.scan('magazine',1);
cashRegister.scan('chocolate',4);
cashRegister.voidLastTransaction();

cashRegister.scan('chocolate',3);
//Void the last transaction and then add 3 instead

//Show the total bill
console.log('Your bill is '+cashRegister.total);